This invention relates generally to devices for preventing or inhibiting the escape of moisture from a beverage preparing apparatus into apparatus for delivering a dry particulate food product to the beverage preparing apparatus.
For example, in recent years there has been much energy devoted to development of combination coffee grinder/brewer machines. The brewing portion of such machines typically utilizes hot water generating means to deliver boiling or nearly boiling water to a spray nozzle arrangement which, in turn, sprays the hot water into a brew basket containing a measured amount of ground coffee. The grinder portion of the machine grinds coffee beans to a desired particulate size, whereupon the ground coffee is delivered by suitable means to a paper filter containing brew basket of the usual, well known type.
A problem that has been encountered using such prior art grinder/brewer arrangements is that hot water vapors resulting from the spraying of hot water into the brew basket tend to escape into the ground coffee delivery system and the grinder itself, often resulting in a considerable mess and necessitating frequent and difficult cleaning operations. This problem is dealt with by the coffee grinder/brewer disclosed in U.S. Pat. No. 4,510,853 issued to S. Takagi on Apr. 16, 1985. The reference device employs a grinder which rotates in a vertical plane within a case to grind coffee and dump the resulting powder into a cone shaped accumulator containing a similarly cone shaped paper filter. After the grinding operation is completed, hot water rises through a pipe and flows into the case to clean the grinder and case walls, after which it flows into the accumulator to mix with the ground coffee in the filter. Liquid coffee is then strained through an orifice into a serving pot. Here, of course, the grinder is rinsed with the same hot water which is used to make liquid coffee after each grinding operation.
Another example is U.S. Pat. No. 4,624,177 issued to N. Ito et al. on Nov. 25, 1986 which discloses a grinder having a brew basket located under the edge of a grinder chamber for receiving ground coffee from a grinder through perforations in a chamber defining wall. A sloping front cover directs ground coffee blown out of the chamber into the basket. A sloping cylindrically shaped cap on the grinder housing permits hot water poured thereon from water lines to run off a sloping tongue into the basket without wetting the grinder or, at least, so it is claimed. It would seem, however, that water vapor from the brew basket could back up through the grinder wall perforations to cause at least some wetting of coffee in the grinder. In any case, the fact that there is no effective vapor tight seal between the brew basket and the grinder while the coffee beverage is being prepared is perceived as a disadvantage.
Lastly, U.S. Pat. No. 4,659,023 issued to H. P. Frei et al. on Apr. 21, 1987, unlike the previously mentioned grinder/brewer arrangements does provide means for keeping moisture from escaping from a coffee brewing chamber into an associated grinder during the brewing operation. The reference device includes a ground coffee proportioning chamber having a flexible resilient wall disposed between a grinder outlet orifice and a brewer. An L-shaped bottom wall part of the proportioning chamber is pivotal between a closed position where it is held by a locking mechanism and an open position wherein a portioned amount of ground coffee is dumped into the brewer. A cam is rotated through an arc to alternately push a spring lever to close the bottom wall part into locking relation with the locking mechanism and pull the spring lever to unlock the bottom wall part from the locking mechanism to dump ground coffee from the proportioning chamber. The cam and grinder are operated by a microswitch which is, in turn, activated by expansion of the flexible wall of the proportioning chamber as the result of the latter becoming filled with the desired amount of ground coffee blown therein from the grinder. Clearly, proper timing and mechanical interaction between the cam, spring lever, pivotal bottom wall part, locking mechanism, flexible resilient proportioning chamber wall and microswitch are critical to proper operation of the reference device. Because of the relative complexity of the reference device, obtaining such proper mechanical interaction repeatedly over many cycles of operation is perceived as substantial problem, quite apart from the shear complexity of the device itself.
By means of my invention, I provide a moisture protection system for a dry particulate food delivery system of a beverage preparing means which substantially overcomes these and other difficulties encountered in the prior art.